From nobody Fri Dec 19 14:08:48 2025 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C9DB413D2BE for ; Wed, 3 Jul 2024 10:07:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720001275; cv=none; b=HRqltLsRkdqRCji8mLggjydpnjIoLD/a847N0hrybPRU2JgvW8gW+QXcOjLRMDb0HVlghdDiwIaw6sGlAgK0NBUPiD8wUwA/QRPoBuYUQaert+uw6h0bbJlGWziAjN3HhCyGB3T0A4zK4do6R/Yo6EwhNzh/UdbTs6uKruZdO8k= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720001275; c=relaxed/simple; bh=rx5RnTU+kGBmxxatiIrk+TX3fJ4/GceRbwqeJB9OxDM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=qWAiyb+Ttk8dXXvLRhHay/C33xOk5oysih18hS6MA0yEinneEYWTJzHzeJ8IqBA163ydjAE7mmqGYM6M7ZHj3Z4WX9MwBnpXM8PpBTCu3mPjCM58E+uxf8RDOBv5xVFZnNzKXBu8ZP2v6YMQ2x5xmcnFJ6ZaWD206Sum9s3O4sg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4B23A1007; Wed, 3 Jul 2024 03:08:18 -0700 (PDT) Received: from e130256.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D507F3F766; Wed, 3 Jul 2024 03:07:52 -0700 (PDT) From: Hongyan Xia To: Tejun Heo Cc: linux-kernel@vger.kernel.org Subject: [PATCH 1/2] sched/uclamp: Delegate uclamp to each sched_class Date: Wed, 3 Jul 2024 11:07:47 +0100 Message-Id: <45e58e2fe1f72d6c095c8824c7da696edfd80bd7.1719999165.git.hongyan.xia2@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" uclamp-related operations are written in core.c in a way that may suggest it is a global thing regardless of sched_class, but we end up checking sched_class->uclamp_enabled, so in reality it is sched_class specific anyway. Remove sched_class->uclamp_enabled and simply delegate uclamp to sched_class->{enqueue,dequeue}_task(). This also removes extra uclamp_enabled checks in uclamp_rq_{inc,dec}(). No functional changes for fair and RT. Signed-off-by: Hongyan Xia Acked-by: Tejun Heo --- kernel/sched/core.c | 14 ++------------ kernel/sched/ext.c | 4 ---- kernel/sched/fair.c | 6 ++---- kernel/sched/rt.c | 7 +++---- kernel/sched/sched.h | 15 +++++++++++---- 5 files changed, 18 insertions(+), 28 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 1092955a7d6e..5c5e5aefca81 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1671,7 +1671,7 @@ static inline void uclamp_rq_dec_id(struct rq *rq, st= ruct task_struct *p, } } =20 -static inline void uclamp_rq_inc(struct rq *rq, struct task_struct *p) +void uclamp_rq_inc(struct rq *rq, struct task_struct *p) { enum uclamp_id clamp_id; =20 @@ -1684,9 +1684,6 @@ static inline void uclamp_rq_inc(struct rq *rq, struc= t task_struct *p) if (!static_branch_unlikely(&sched_uclamp_used)) return; =20 - if (unlikely(!p->sched_class->uclamp_enabled)) - return; - for_each_clamp_id(clamp_id) uclamp_rq_inc_id(rq, p, clamp_id); =20 @@ -1695,7 +1692,7 @@ static inline void uclamp_rq_inc(struct rq *rq, struc= t task_struct *p) rq->uclamp_flags &=3D ~UCLAMP_FLAG_IDLE; } =20 -static inline void uclamp_rq_dec(struct rq *rq, struct task_struct *p) +void uclamp_rq_dec(struct rq *rq, struct task_struct *p) { enum uclamp_id clamp_id; =20 @@ -1708,9 +1705,6 @@ static inline void uclamp_rq_dec(struct rq *rq, struc= t task_struct *p) if (!static_branch_unlikely(&sched_uclamp_used)) return; =20 - if (unlikely(!p->sched_class->uclamp_enabled)) - return; - for_each_clamp_id(clamp_id) uclamp_rq_dec_id(rq, p, clamp_id); } @@ -1949,8 +1943,6 @@ static void __init init_uclamp(void) } =20 #else /* !CONFIG_UCLAMP_TASK */ -static inline void uclamp_rq_inc(struct rq *rq, struct task_struct *p) { } -static inline void uclamp_rq_dec(struct rq *rq, struct task_struct *p) { } static inline void uclamp_fork(struct task_struct *p) { } static inline void uclamp_post_fork(struct task_struct *p) { } static inline void init_uclamp(void) { } @@ -1990,7 +1982,6 @@ void enqueue_task(struct rq *rq, struct task_struct *= p, int flags) psi_enqueue(p, (flags & ENQUEUE_WAKEUP) && !(flags & ENQUEUE_MIGRATED)); } =20 - uclamp_rq_inc(rq, p); p->sched_class->enqueue_task(rq, p, flags); =20 if (sched_core_enabled(rq)) @@ -2010,7 +2001,6 @@ void dequeue_task(struct rq *rq, struct task_struct *= p, int flags) psi_dequeue(p, flags & DEQUEUE_SLEEP); } =20 - uclamp_rq_dec(rq, p); p->sched_class->dequeue_task(rq, p, flags); } =20 diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index ae9ec8f542f2..0b120104a7ce 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -3520,10 +3520,6 @@ DEFINE_SCHED_CLASS(ext) =3D { .prio_changed =3D prio_changed_scx, =20 .update_curr =3D update_curr_scx, - -#ifdef CONFIG_UCLAMP_TASK - .uclamp_enabled =3D 1, -#endif }; =20 static void init_dsq(struct scx_dispatch_q *dsq, u64 dsq_id) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index d59537416865..a861fafd53f9 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6752,6 +6752,7 @@ enqueue_task_fair(struct rq *rq, struct task_struct *= p, int flags) int idle_h_nr_running =3D task_has_idle_policy(p); int task_new =3D !(flags & ENQUEUE_WAKEUP); =20 + uclamp_rq_inc(rq, p); /* * The code below (indirectly) updates schedutil which looks at * the cfs_rq utilization to select a frequency. @@ -6846,6 +6847,7 @@ static void dequeue_task_fair(struct rq *rq, struct t= ask_struct *p, int flags) int idle_h_nr_running =3D task_has_idle_policy(p); bool was_sched_idle =3D sched_idle_rq(rq); =20 + uclamp_rq_dec(rq, p); util_est_dequeue(&rq->cfs, p); =20 for_each_sched_entity(se) { @@ -13227,10 +13229,6 @@ DEFINE_SCHED_CLASS(fair) =3D { #ifdef CONFIG_SCHED_CORE .task_is_throttled =3D task_is_throttled_fair, #endif - -#ifdef CONFIG_UCLAMP_TASK - .uclamp_enabled =3D 1, -#endif }; =20 #ifdef CONFIG_SCHED_DEBUG diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 63e49c8ffc4d..f0b3ba5e8867 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1480,6 +1480,8 @@ enqueue_task_rt(struct rq *rq, struct task_struct *p,= int flags) { struct sched_rt_entity *rt_se =3D &p->rt; =20 + uclamp_rq_inc(rq, p); + if (flags & ENQUEUE_WAKEUP) rt_se->timeout =3D 0; =20 @@ -1496,6 +1498,7 @@ static void dequeue_task_rt(struct rq *rq, struct tas= k_struct *p, int flags) { struct sched_rt_entity *rt_se =3D &p->rt; =20 + uclamp_rq_dec(rq, p); update_curr_rt(rq); dequeue_rt_entity(rt_se, flags); =20 @@ -2680,10 +2683,6 @@ DEFINE_SCHED_CLASS(rt) =3D { #ifdef CONFIG_SCHED_CORE .task_is_throttled =3D task_is_throttled_rt, #endif - -#ifdef CONFIG_UCLAMP_TASK - .uclamp_enabled =3D 1, -#endif }; =20 #ifdef CONFIG_RT_GROUP_SCHED diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 963a2fa180ad..619b1cc972bd 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -2340,10 +2340,6 @@ extern s64 update_curr_common(struct rq *rq); =20 struct sched_class { =20 -#ifdef CONFIG_UCLAMP_TASK - int uclamp_enabled; -#endif - void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); void (*yield_task) (struct rq *rq); @@ -3246,6 +3242,9 @@ uclamp_se_set(struct uclamp_se *uc_se, unsigned int v= alue, bool user_defined) uc_se->user_defined =3D user_defined; } =20 +void uclamp_rq_inc(struct rq *rq, struct task_struct *p); +void uclamp_rq_dec(struct rq *rq, struct task_struct *p); + #else /* !CONFIG_UCLAMP_TASK: */ =20 static inline unsigned long @@ -3283,6 +3282,14 @@ static inline bool uclamp_rq_is_idle(struct rq *rq) return false; } =20 +static inline void uclamp_rq_inc(struct rq *rq, struct task_struct *p) +{ +} + +static inline void uclamp_rq_dec(struct rq *rq, struct task_struct *p) +{ +} + #endif /* !CONFIG_UCLAMP_TASK */ =20 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ --=20 2.34.1